They must occur in the DNA, which is in each cells nucleus. More specifically the nucleolus of the cell. A mutation occurs in an allele, where a base triplet (or a codon) gets transcribed incorrectly.
Answer: Although all organic compounds contain carbon, and almost all have hydrogen, most of them contain other elements as well. The most common other elements in organic compounds are oxygen, nitrogen, sulfur, and the halogens.
Explanation: hope this helps
Treatment
Meningitis is an infection of the membranes, meninges that surrounds and protects the central nervous system (the brain and spinal cord). Bacterial meningitis must be treated immediately with intravenous antibiotics and sometimes corticosteroids and, of course, the antibiotic depends on the type of bacteria causing the infection.
Prevention
First of all, to prevent the spread of bacterial meningitis it is important to practice good hygiene, such as frequent handwashing. Since the factors that increase the risk include spending time in communities (school, campus or college) because it spreads easily, children should be aware and vaccinated. As several types of bacteria can cause bacterial meningitis, a range of vaccines is wide (e.g. meningococcal vaccine, Hib vaccine).
What is barbules and pinnae?